“If something like this ever happens again,” she said, “and you can’t reach anyone, post it on Twitter.” I’d started using Twitter a couple of years earlier, and now had some 135,000 followers, many of them journalists, government officials, and politicians from around the world. I followed her instructions, tweeting: “Urgent: Just was arrested by Spanish police in Madrid on a Russian Interpol arrest warrant. Going to the police station right now.”